US4729962A - Semiconductor junction formation by directed heat - Google Patents
Semiconductor junction formation by directed heat Download PDFInfo
- Publication number
- US4729962A US4729962A US06/843,486 US84348686A US4729962A US 4729962 A US4729962 A US 4729962A US 84348686 A US84348686 A US 84348686A US 4729962 A US4729962 A US 4729962A
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- US
- United States
- Prior art keywords
- web
- type
- high intensity
- dopant
- face
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
- 239000004065 semiconductor Substances 0.000 title claims abstract description 9
- 230000015572 biosynthetic process Effects 0.000 title description 4
- 239000002019 doping agent Substances 0.000 claims abstract description 12
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims abstract description 9
- 238000000034 method Methods 0.000 claims abstract description 9
- 229910052710 silicon Inorganic materials 0.000 claims abstract description 9
- 239000010703 silicon Substances 0.000 claims abstract description 9
- 239000002904 solvent Substances 0.000 claims abstract description 7
- 239000012705 liquid precursor Substances 0.000 claims description 7
- 238000010438 heat treatment Methods 0.000 claims description 6
- 238000000137 annealing Methods 0.000 claims description 5
- 238000001816 cooling Methods 0.000 claims description 2
- 230000007547 defect Effects 0.000 claims description 2
- 239000011248 coating agent Substances 0.000 claims 2
- 238000000576 coating method Methods 0.000 claims 2
- 239000002243 precursor Substances 0.000 abstract description 4
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 5
- 229910052736 halogen Inorganic materials 0.000 description 4
- 229910052721 tungsten Inorganic materials 0.000 description 4
- 239000010937 tungsten Substances 0.000 description 4
- -1 tungsten halogen Chemical class 0.000 description 4
- 238000009529 body temperature measurement Methods 0.000 description 2
- 235000012239 silicon dioxide Nutrition 0.000 description 2
- 239000000377 silicon dioxide Substances 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- 238000005229 chemical vapour deposition Methods 0.000 description 1
- 238000004140 cleaning Methods 0.000 description 1
- 229910052681 coesite Inorganic materials 0.000 description 1
- 238000011109 contamination Methods 0.000 description 1
- 229910052906 cristobalite Inorganic materials 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 239000006260 foam Substances 0.000 description 1
- 230000000873 masking effect Effects 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000005499 meniscus Effects 0.000 description 1
- 230000001737 promoting effect Effects 0.000 description 1
- 239000010453 quartz Substances 0.000 description 1
- 229910052682 stishovite Inorganic materials 0.000 description 1
- 229910052905 tridymite Inorganic materials 0.000 description 1
Images
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/26—Bombardment with radiation
- H01L21/263—Bombardment with radiation with high-energy radiation
- H01L21/268—Bombardment with radiation with high-energy radiation using electromagnetic radiation, e.g. laser radiation
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/02—Manufacture or treatment of semiconductor devices or of parts thereof
- H01L21/04—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer
- H01L21/18—Manufacture or treatment of semiconductor devices or of parts thereof the devices having potential barriers, e.g. a PN junction, depletion layer or carrier concentration layer the devices having semiconductor bodies comprising elements of Group IV of the Periodic Table or AIIIBV compounds with or without impurities, e.g. doping materials
- H01L21/22—Diffusion of impurity materials, e.g. doping materials, electrode materials, into or out of a semiconductor body, or between semiconductor regions; Interactions between two or more impurities; Redistribution of impurities
- H01L21/225—Diffusion of impurity materials, e.g. doping materials, electrode materials, into or out of a semiconductor body, or between semiconductor regions; Interactions between two or more impurities; Redistribution of impurities using diffusion into or out of a solid from or into a solid phase, e.g. a doped oxide layer
- H01L21/2251—Diffusion into or out of group IV semiconductors
- H01L21/2254—Diffusion into or out of group IV semiconductors from or through or into an applied layer, e.g. photoresist, nitrides
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S148/00—Metal treatment
- Y10S148/014—Capacitor
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10S148/00—Metal treatment
- Y10S148/093—Laser beam treatment in general
Definitions
- This invention pertains to the art of semiconductor junction formation.
- junctions in silicon webs such as dendritic silicon webs for use as photovoltaic solar cells, for example, is typically carried out in a tube-type or belt-type diffusion furnace. If junctions are to be formed in both faces of the web, a two-step process is required in which a dopant layer is first diffused into one face, the face is then cleaned and masked as with silicon dioxide, SiO 2 , to prevent cross-over of dopant from the diffused layer to the to-be-diffused layer at the opposite face and then, in a separate operation, another dopant layer is diffused into the opposite face.
- the heat-up to, say, 850°-950° C. and the subsequent cool-down for each separate layer may typically take 40 minutes or so.
- An important aspect of the invention is that the heat required to diffuse in the dopants is supplied by a relatively short duration pulse of high intensity light.
- the method according to the invention for forming one or more semiconductor junctions in a silicon web of a given P- or N-type includes applying a liquid precursor containing a dopant of a desired P- or N-type to at least one face of the web, baking the web sufficiently to remove excess solvent, and then heating the web rapidly with a pulsed high intensity light for a period of less than a minute at temperatures in a range from about 950° C. to 1200° C.
- FIG. 1 is a simplified edge view of a web to which liquid precursors containing dopants is being applied to opposite faces of the web;
- FIG. 2 is a simplified view of the web of FIG. 1 in an oven for baking;
- FIG. 3 is a simplified face view of the doped web located in a pulse high intensity light device for undergoing the rapid heating step
- FIG. 4 is a simplified view of the web of FIG. 3 in an annealing oven.
- a predoped, P-type, dendritic silicon web 2 has a liquid precursor 4 containing an N-type dopant to one face of the web 2 and a liquid precursor 6 containing a P-type dopant is applied to the opposite face of the web 2.
- the liquid precursors may be applied in conventional fashion such as by using a foam brush 8, a meniscus coater or by a chemical vapor deposition method. Examples of the precursors which may be used are those which are commercially available, such as Allied Chemical Corp. P8 or Filmtronics, Inc. P2.5 for the precursor of the N-type, and Allied Chemical Corp. B150 for the P-type.
- the web 2 with the applied precursors 4 and 6 is then baked in an oven 10 (FIG. 2) to remove the excess solvent from the faces of the web.
- the oven 10 may be an air environment oven which is heated to approximately 200° C. and the web is heated at that temperature for, say, 20 minutes or so to remove the excess solvent.
- the next step in the process is the rapid heating of the doped web by a pulsed high intensity light in a mechanism 12 as schematically shown in FIG. 3.
- the rapid thermal heater 12 of FIG. 3 is a tungsten halogen system such as is commercially available, for example, from A. G. Associates of Palo Alto, Calif. As publicly disclosed by this entity, the tungsten halogen system uses banks of tungsten halogen lamps 14 positioned above and below the web which, in the A. G. Associates' heat pulsed mechanism is placed in a quartz tube 16 for promoting thermal efficiency.
- the web 2 is heated inside the mechanism 12 by pulsed high intensity light from the tungsten halogen lamps for a period of less than a minute at temperatures in a range from about 1000° C. to 1150° C. to simultaneously form junctions in both faces of the web.
- the preferred temperature and time for forming simultaneous junctions in both faces of the dendritic silicon web for use in solar cells is 950° C. to 1200° C. for about 5-15 seconds. This produces relatively shallow junctions which are preferable for solar cells. To obtain deeper junctions for other devices such as rectifiers and transistors, etc., the time and temperature may be increased proportionately.
- thermocouple 18 may be embedded in web material 20 thermally similar to the web 20, as suggested by A. G. Associates. It will be apparent that other temperature measurement and control system may also be used in carrying out the invention.
- the doping which takes place in the rapid thermal processing occurs more quickly than a period of time which would permit cross-over of the dopant from one face of the web to the other face of the web and thereby permit contamination.
- the inventive process only a single step is required in the doping so that the complicated and expensive two-step process of the conventional prior art is avoided, along with the cleaning and masking.
- the annealing is known to be able to take out defects in the web which are frozen in during too rapid cooling of the web.
- the annealing is done to provide for higher efficiencies for solar cells and to provide for higher carrier lifetimes for other semiconductors.
- the annealing may take place in an air environment oven 22 of FIG. 4 and in which the web 2 is heated in air at 750° C. to 850° C. for anywhere from 10 to 60 minutes.
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- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Microelectronics & Electronic Packaging (AREA)
- General Physics & Mathematics (AREA)
- Manufacturing & Machinery (AREA)
- Computer Hardware Design (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Power Engineering (AREA)
- High Energy & Nuclear Physics (AREA)
- Electromagnetism (AREA)
- Optics & Photonics (AREA)
- Health & Medical Sciences (AREA)
- Toxicology (AREA)
- Photovoltaic Devices (AREA)
Abstract
Description
Claims (1)
Priority Applications (5)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US06/843,486 US4729962A (en) | 1986-03-24 | 1986-03-24 | Semiconductor junction formation by directed heat |
FR8616556A FR2596201A1 (en) | 1986-03-24 | 1986-11-27 | METHOD FOR MANUFACTURING SEMICONDUCTOR JUNCTIONS AND PRODUCTS THUS OBTAINED |
GB8628541A GB2188481B (en) | 1986-03-24 | 1986-11-28 | Method of forming semiconductor junctions |
DE19863640713 DE3640713A1 (en) | 1986-03-24 | 1986-11-28 | METHOD FOR FORMING SEMICONDUCTOR TRANSITIONS |
JP61316136A JP2610853B2 (en) | 1986-03-24 | 1986-12-26 | Semiconductor junction formation method |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US06/843,486 US4729962A (en) | 1986-03-24 | 1986-03-24 | Semiconductor junction formation by directed heat |
Publications (1)
Publication Number | Publication Date |
---|---|
US4729962A true US4729962A (en) | 1988-03-08 |
Family
ID=25290132
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US06/843,486 Expired - Fee Related US4729962A (en) | 1986-03-24 | 1986-03-24 | Semiconductor junction formation by directed heat |
Country Status (5)
Country | Link |
---|---|
US (1) | US4729962A (en) |
JP (1) | JP2610853B2 (en) |
DE (1) | DE3640713A1 (en) |
FR (1) | FR2596201A1 (en) |
GB (1) | GB2188481B (en) |
Cited By (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5278097A (en) * | 1989-07-31 | 1994-01-11 | Texas Instruments Incorporated | Method of making doped silicon spheres |
US5395794A (en) * | 1993-04-22 | 1995-03-07 | Sklyarevich; Vladislav E. | Method of treating semiconductor materials |
US5399523A (en) * | 1991-03-26 | 1995-03-21 | Siemens Aktiengesellscaft | Method for the rapid thermal processing of a semiconductor wafer by irradiation |
WO1996008043A1 (en) * | 1994-09-09 | 1996-03-14 | Georgia Tech Research Corporation | Processes for producing low cost, high efficiency silicon solar cells |
US5527389A (en) * | 1992-08-07 | 1996-06-18 | Ase Americas, Inc. | Apparatus for forming diffusion junctions in solar cell substrates |
US6143633A (en) * | 1995-10-05 | 2000-11-07 | Ebara Solar, Inc. | In-situ diffusion of dopant impurities during dendritic web growth of crystal ribbon |
Families Citing this family (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE4331937A1 (en) * | 1993-09-16 | 1994-03-17 | Ulrich Prof Dr Mohr | Dopant diffusion into solid-state semiconductor body - by coating surface with medium containing dopant and applying voltage between electrodes connected to medium and semiconductor body |
MY179365A (en) * | 2015-02-25 | 2020-11-05 | Toray Industries | P-type impurity-diffusing composition, method for manufacturing semiconductor device using said composition, solar cell, and method for manufacturing said solar cell |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3940289A (en) * | 1975-02-03 | 1976-02-24 | The United States Of America As Represented By The Secretary Of The Navy | Flash melting method for producing new impurity distributions in solids |
US4273950A (en) * | 1979-05-29 | 1981-06-16 | Photowatt International, Inc. | Solar cell and fabrication thereof using microwaves |
JPS5948402A (en) * | 1982-09-14 | 1984-03-19 | Asahi Chem Ind Co Ltd | Portable insecticidal mat |
US4443493A (en) * | 1980-04-28 | 1984-04-17 | Fairchild Camera And Instrument Corp. | Laser induced flow glass materials |
US4482393A (en) * | 1979-12-17 | 1984-11-13 | Sony Corporation | Method of activating implanted ions by incoherent light beam |
US4514440A (en) * | 1983-12-12 | 1985-04-30 | Allied Corporation | Spin-on dopant method |
US4539431A (en) * | 1983-06-06 | 1985-09-03 | Sera Solar Corporation | Pulse anneal method for solar cell |
US4619036A (en) * | 1984-09-28 | 1986-10-28 | Texas Instruments Incorporated | Self-aligned low-temperature emitter drive-in |
US4621411A (en) * | 1984-09-28 | 1986-11-11 | Texas Instruments Incorporated | Laser-enhanced drive in of source and drain diffusions |
Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5552221A (en) * | 1978-10-12 | 1980-04-16 | Toshiba Corp | Impurity dispersion method and its device |
JPS55127016A (en) * | 1979-03-26 | 1980-10-01 | Hitachi Ltd | Manufacturing of semiconductor device |
FR2507822A1 (en) * | 1979-05-29 | 1982-12-17 | Photowatt International | Polycrystalline silicon solar cells prodn. - by exposing to unipolar microwaves to diffuse dopant |
CA1177148A (en) * | 1981-10-06 | 1984-10-30 | Robert J. Mcintyre | Avalanche photodiode array |
US4571366A (en) * | 1982-02-11 | 1986-02-18 | Owens-Illinois, Inc. | Process for forming a doped oxide film and doped semiconductor |
JPS58186933A (en) * | 1982-04-23 | 1983-11-01 | Sharp Corp | Preparation of semiconductor device |
JPS58223320A (en) * | 1982-06-22 | 1983-12-24 | Ushio Inc | Diffusing method for impurity |
DE3340874A1 (en) * | 1983-11-11 | 1985-05-23 | Telefunken electronic GmbH, 7100 Heilbronn | METHOD FOR PRODUCING A SOLAR CELL |
US4521441A (en) * | 1983-12-19 | 1985-06-04 | Motorola, Inc. | Plasma enhanced diffusion process |
-
1986
- 1986-03-24 US US06/843,486 patent/US4729962A/en not_active Expired - Fee Related
- 1986-11-27 FR FR8616556A patent/FR2596201A1/en active Pending
- 1986-11-28 GB GB8628541A patent/GB2188481B/en not_active Expired
- 1986-11-28 DE DE19863640713 patent/DE3640713A1/en not_active Ceased
- 1986-12-26 JP JP61316136A patent/JP2610853B2/en not_active Expired - Lifetime
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US3940289A (en) * | 1975-02-03 | 1976-02-24 | The United States Of America As Represented By The Secretary Of The Navy | Flash melting method for producing new impurity distributions in solids |
US4273950A (en) * | 1979-05-29 | 1981-06-16 | Photowatt International, Inc. | Solar cell and fabrication thereof using microwaves |
US4482393A (en) * | 1979-12-17 | 1984-11-13 | Sony Corporation | Method of activating implanted ions by incoherent light beam |
US4443493A (en) * | 1980-04-28 | 1984-04-17 | Fairchild Camera And Instrument Corp. | Laser induced flow glass materials |
JPS5948402A (en) * | 1982-09-14 | 1984-03-19 | Asahi Chem Ind Co Ltd | Portable insecticidal mat |
US4539431A (en) * | 1983-06-06 | 1985-09-03 | Sera Solar Corporation | Pulse anneal method for solar cell |
US4514440A (en) * | 1983-12-12 | 1985-04-30 | Allied Corporation | Spin-on dopant method |
US4619036A (en) * | 1984-09-28 | 1986-10-28 | Texas Instruments Incorporated | Self-aligned low-temperature emitter drive-in |
US4621411A (en) * | 1984-09-28 | 1986-11-11 | Texas Instruments Incorporated | Laser-enhanced drive in of source and drain diffusions |
Non-Patent Citations (3)
Title |
---|
Kato et al., Jour. Electrochem. Soc. (Jul. 1985), p. 1730. * |
Sedwick, Jour. Electrochem. Soc. 130 (1983), 484. * |
USAMI et al., 18th Photovoltiaic . . . Conf., Las Vegas, Nevada, Oct. 1985. * |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5278097A (en) * | 1989-07-31 | 1994-01-11 | Texas Instruments Incorporated | Method of making doped silicon spheres |
US5399523A (en) * | 1991-03-26 | 1995-03-21 | Siemens Aktiengesellscaft | Method for the rapid thermal processing of a semiconductor wafer by irradiation |
US5527389A (en) * | 1992-08-07 | 1996-06-18 | Ase Americas, Inc. | Apparatus for forming diffusion junctions in solar cell substrates |
US5395794A (en) * | 1993-04-22 | 1995-03-07 | Sklyarevich; Vladislav E. | Method of treating semiconductor materials |
WO1996008043A1 (en) * | 1994-09-09 | 1996-03-14 | Georgia Tech Research Corporation | Processes for producing low cost, high efficiency silicon solar cells |
US5510271A (en) * | 1994-09-09 | 1996-04-23 | Georgia Tech Research Corporation | Processes for producing low cost, high efficiency silicon solar cells |
US6143633A (en) * | 1995-10-05 | 2000-11-07 | Ebara Solar, Inc. | In-situ diffusion of dopant impurities during dendritic web growth of crystal ribbon |
Also Published As
Publication number | Publication date |
---|---|
JP2610853B2 (en) | 1997-05-14 |
GB2188481B (en) | 1989-12-20 |
GB8628541D0 (en) | 1987-01-07 |
JPS62226671A (en) | 1987-10-05 |
FR2596201A1 (en) | 1987-09-25 |
DE3640713A1 (en) | 1987-10-08 |
GB2188481A (en) | 1987-09-30 |
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Owner name: WESTINGHOUSE ELECTRIC CORPORATION, WESTINGHOUSE BU Free format text: ASSIGNMENT OF ASSIGNORS INTEREST.;ASSIGNOR:CAMPBELL, ROBERT B.;REEL/FRAME:004531/0472 Effective date: 19860310 |
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